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  2. Phenylalanine - Wikipedia

    en.wikipedia.org/wiki/Phenylalanine

    Phenylalanine (symbol Phe or F) [3] is an essential α-amino acid with the formula C 9 H 11 NO 2.It can be viewed as a benzyl group substituted for the methyl group of alanine, or a phenyl group in place of a terminal hydrogen of alanine.

  3. Pi-interaction - Wikipedia

    en.wikipedia.org/wiki/Pi-interaction

    In chemistry, π-effects or π-interactions are a type of non-covalent interaction that involves π systems.Just like in an electrostatic interaction where a region of negative charge interacts with a positive charge, the electron-rich π system can interact with a metal (cationic or neutral), an anion, another molecule and even another π system. [1]

  4. Cation–π interaction - Wikipedia

    en.wikipedia.org/wiki/Cation–π_interaction

    The cation–π interaction is noncovalent and is therefore fundamentally different than bonding between transition metals and π systems. Transition metals have the ability to share electron density with π-systems through d-orbitals, creating bonds that are highly covalent in character and cannot be modeled as a cation–π interaction.

  5. Covalent bond - Wikipedia

    en.wikipedia.org/wiki/Covalent_bond

    In organic chemistry, covalent bonding is much more common than ionic bonding. Covalent bonding also includes many kinds of interactions, including σ-bonding, π-bonding, metal-to-metal bonding, agostic interactions, bent bonds, three-center two-electron bonds and three-center four-electron bonds. [2] [3] The term covalent bond dates from 1939 ...

  6. Chemical polarity - Wikipedia

    en.wikipedia.org/wiki/Chemical_polarity

    The terms "polar" and "nonpolar" are usually applied to covalent bonds, that is, bonds where the polarity is not complete. To determine the polarity of a covalent bond using numerical means, the difference between the electronegativity of the atoms is used.

  7. Lone pair - Wikipedia

    en.wikipedia.org/wiki/Lone_pair

    In contrast to NH 3, NF 3 has a much lower dipole moment of 0.234 D. Fluorine is more electronegative than nitrogen and the polarity of the N-F bonds is opposite to that of the N-H bonds in ammonia, so that the dipole due to the lone pair opposes the N-F bond dipoles, resulting in a low molecular dipole moment.

  8. Pauling's principle of electroneutrality - Wikipedia

    en.wikipedia.org/wiki/Pauling's_principle_of...

    On the other hand, a covalent linkage would lead to a charge of -3 on the metal and +1 on each of the nitrogen atoms in the ammonia molecules. Using the electroneutrality principle the assumption is made that the Co-N bond will have 50% ionic character thus resulting in a zero charge on the cobalt atom.

  9. Intramolecular force - Wikipedia

    en.wikipedia.org/wiki/Intramolecular_force

    In a true covalent bond, the electrons are shared evenly between the two atoms of the bond; there is little or no charge separation. Covalent bonds are generally formed between two nonmetals. There are several types of covalent bonds: in polar covalent bonds , electrons are more likely to be found around one of the two atoms, whereas in ...